// Copyright 2015 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "cc/layers/painted_scrollbar_layer.h"

#include "cc/animation/animation_host.h"
#include "cc/test/fake_layer_tree_host.h"
#include "cc/test/fake_layer_tree_host_client.h"
#include "cc/test/fake_scrollbar.h"
#include "cc/test/test_task_graph_runner.h"
#include "testing/gmock/include/gmock/gmock.h"

using ::testing::_;
using ::testing::Mock;

namespace cc {

namespace {

    class MockScrollbar : public FakeScrollbar {
    public:
        MockScrollbar()
            : FakeScrollbar(true, true, true)
        {
        }
        MOCK_METHOD3(PaintPart,
            void(SkCanvas* canvas,
                ScrollbarPart part,
                const gfx::Rect& content_rect));
    };

    TEST(PaintedScrollbarLayerTest, NeedsPaint)
    {
        FakeLayerTreeHostClient fake_client_;
        TestTaskGraphRunner task_graph_runner_;

        auto animation_host = AnimationHost::CreateForTesting(ThreadInstance::MAIN);
        auto layer_tree_host = FakeLayerTreeHost::Create(
            &fake_client_, &task_graph_runner_, animation_host.get());

        MockScrollbar* scrollbar = new MockScrollbar();
        scoped_refptr<PaintedScrollbarLayer> scrollbar_layer = PaintedScrollbarLayer::Create(std::unique_ptr<Scrollbar>(scrollbar), 1);

        scrollbar_layer->SetIsDrawable(true);
        scrollbar_layer->SetBounds(gfx::Size(100, 100));

        layer_tree_host->SetRootLayer(scrollbar_layer);
        EXPECT_EQ(scrollbar_layer->GetLayerTreeHostForTesting(),
            layer_tree_host.get());
        scrollbar_layer->SavePaintProperties();

        // Request no paint, but expect them to be painted because they have not
        // yet been initialized.
        scrollbar->set_needs_paint_thumb(false);
        scrollbar->set_needs_paint_track(false);
        EXPECT_CALL(*scrollbar, PaintPart(_, THUMB, _)).Times(1);
        EXPECT_CALL(*scrollbar, PaintPart(_, TRACK, _)).Times(1);
        scrollbar_layer->Update();
        Mock::VerifyAndClearExpectations(scrollbar);

        // The next update will paint nothing because the first update caused a paint.
        EXPECT_CALL(*scrollbar, PaintPart(_, THUMB, _)).Times(0);
        EXPECT_CALL(*scrollbar, PaintPart(_, TRACK, _)).Times(0);
        scrollbar_layer->Update();
        Mock::VerifyAndClearExpectations(scrollbar);

        // Enable the thumb.
        EXPECT_CALL(*scrollbar, PaintPart(_, THUMB, _)).Times(1);
        EXPECT_CALL(*scrollbar, PaintPart(_, TRACK, _)).Times(0);
        scrollbar->set_needs_paint_thumb(true);
        scrollbar->set_needs_paint_track(false);
        scrollbar_layer->Update();
        Mock::VerifyAndClearExpectations(scrollbar);

        // Enable the track.
        EXPECT_CALL(*scrollbar, PaintPart(_, THUMB, _)).Times(0);
        EXPECT_CALL(*scrollbar, PaintPart(_, TRACK, _)).Times(1);
        scrollbar->set_needs_paint_thumb(false);
        scrollbar->set_needs_paint_track(true);
        scrollbar_layer->Update();
        Mock::VerifyAndClearExpectations(scrollbar);
    }

} // namespace
} // namespace cc
